UH to study Saddle water resources

Previous scientific studies of Hawaii Island’s fresh water resources have shown some of what scientists thought they knew about water here was wrong.

A University of Hawaii professor got environmental approval this week to take a look at the Humuula Saddle region for more information about groundwater there.

“Any information would be good to have,” Donald Thomas, of the Hawaii Institute of Geophysics and Planetology, said. “This is an area we have very little information about. In prior work we’ve done, we’ve found we don’t fully understand the hydrology (of Hawaii Island). We’ve found resources that weren’t supposed to exist.”

A 1993 drilling project found an artesian groundwater aquifer more than 1,000 feet below sea level, said the environmental assessment, which was given a finding of no significant impact this month by the University of Hawaii. That aquifer’s presence contradicted scientific literature discounting the likelihood of Hawaii Island having any artesian water, the document said. Another research effort, done about a mile inland from the initial borehole location, found an artesian aquifer at about the same depth.

Many of the assumptions scientists and government officials have now about Hawaii’s aquifer aren’t based on good information, Thomas said. His project, which should begin in late October or early November, and wrap up within about a year, will use drills to bring up fluid samples from two sites in the saddle between Mauna Loa and Mauna Kea, on state land presently leased to the U.S. Army.

Screening criteria for drilling technology included technology that “provides detailed stratigraphic and geologic information on the area of investigation; (and) provides an opportunity to detect groundwater saturation conditions while drilling.”

The project will help scientists “develop a better understanding of the groundwater system contained within Mauna Kea,” as well as help scientists “to confirm the elevation of the water table within the Saddle region; to document the geologic structures overall as well as those that impact the groundwater system; and to conduct sampling and analysis of water samples in order to determine their source(s), their chemical compositions, and their ages/residence times in the Saddle aquifer(s),” the environmental assessment said.

Finding more water sources could open the Humuula Saddle region up for more farming and ranching, Thomas said, something large area landowner Department of Hawaiian Home Lands has expressed interest in.

“Basically, if it turns out there’s a lot of water there, that says perhaps the farmers and ranchers can make use of that water,” Thomas said. “One of (DHHL’s) biggest concerns is availability of water for their lessees. This puts more Hawaiians on the land.”

Thomas said his findings will be published and made available to the public. He’s also planning on creating a website, to be updated periodically during the drilling phase, with information about what scientists are discovering, he said.